1. Field of the Invention
The present invention relates to ventilators and louvers for use in ventilating buildings, and more particularly to such devices as have a plurality of louver blades secured within an outer frame. More specifically, the present invention relates to a multi-bladed louver that is designed and constructed to be readily assembled, from component parts without the use of welding.
2. Description of the Prior Art
Louvers have long been used in association with air handling and ventilation equipment to permit the intake and exhaust of air from buildings. Conventionally, louvers have comprised a plurality of metal louver blades secured within an outer metal frame of generally rectangular shape. Louvers normally range in size from eighteen inches up to forty-eight inches in height, with similar ranges in width.
The attachment of the louver blades to the outer support frame traditionally has been accomplished by using such fasteners as nails, rivets or screws. More recently the lower blades have been individually attached to the outer frame by spot welding. Fabrication of the louvered vents begins with a galvanized metal sheet that is cut into a variety of blade patterns. Each blade is further provided with a variety of slots and projections, permitting the various component parts to be fit together.
In addition to the tedium of making all of these exacting fabrication cuts, the one-by-one attachment of each member to the frame requires one or more spot welds to retain that member in place. Spot welding not only requires expensive equipment and further processing steps, the intense heating required also affects the ability of the galvanized metal to resist corrosion.
A variety of louver fabrication techniques are suggested in the prior art towards limiting the amount of fastening steps required to secure the louvers to the outer frame. The use of tabs formed in the outer frames is suggested by Minds, Jr., U.S. Pat. No. 3,339,330, with the tab spacing somewhat less than the louver width, resulting in the biasing force exerted against the tabs by the louvers intended to secure and maintain the louvers in position. In Roth, U.S. Pat. No. 5,254,034, the louver blade consists of two blade members slidably engaged with one-another, with screws used to attached each of the blades to a respective frame member.
The ventilating louver of Tarnoff, U.S. Pat. No. 3,422,744, makes use of projecting longitudinal supports formed in the outer frame, with the louvers received within spaced-apart slots that are formed in the supports. The slots are staggered between the fore and aft supports, permitting a flat louver inserted within the slots to obtain a desired, slanted orientation within the frame.
Ideally, a ventilation louver would be constructed out of easily-formed pieces of sheet metal that, when brought together, form an interlocking construction requiring few if any fasteners or welding operations to complete a finished unit.